This invention relates to a joining system for fixedly joining at least two elements, in particular beams and girders, comprising at least one first element which at one of its ends is adjacent to the other element on a contact face and is attached thereto by a joining means and at least one connection part, which is attached to one of the elements, in particular by being integrated into it, and is in particular a shear connector made of a high-strength material, preferably a metal.
A joining system of the generic type is known from German Patent DE 197 01 458 C1. The joining systems described there have proven especially suitable in wood construction. To ensure a stable joint, a supporting beam is dividedxe2x80x94usually at the centerxe2x80x94and a recess is cut into the interior of the beam. The cross-sectional contour of the recess corresponds to that of a metal shear connector, which is integrated into the beam. For the purpose of a secure hold, the shear connector is equipped with a plurality of mandrels which correspond to a complementary pattern of holes in the beam. Threaded boreholes are cut in the shear connector so that a connecting part can be attached fixedly by screws.
Joining systems of the type known previously, however, occasionally reach the limit of their assembly capacity. When space is limited, it may be difficult under some circumstances to manufacture the beam connector because there is not enough space and thus there is not enough accessibility to attach screws from the outside to a girder equipped with a shear connector.
Therefore, the object of this invention is to improve upon a joining system of the generic type, to permit a simplified and inexpensive method of mounting beams equipped with a shear connector onto any connecting elements.
The method of achieving this object is characterized according to this invention in that the connecting part, in particular the shear connector, is provided with a continuous recess, in particular a borehole, and the joining means extend through the recess, whereby the element accommodating the connecting part is designed as a wooden component. Due to this design there are novel and advantageous possibilities for joining systems, as explained below.
The connecting part in the form of the shear connector, which was previously already known as such, has a plurality of projections, i.e., mandrels, for integrally anchoring in one of the elements. Frequently the element receiving the connecting part is designed as a beam. As is already known, the element accommodating the shear connector may be designed to be divisible for insertion of the shear connector, preferably divisible in its central plane. However, division in a plane in which the tensile or compressive zone of the beam is located is also possible; in this manner, the beam force is introduced into the shear connector in the best possible manner and transmitted by it.
According to one refinement of this invention, the joining means for attachment to the other element is equipped with an end section which cooperates with an opposing section in or on the other element in a form-fitting manner. This refers in particular to a spherical or hook-shaped end section of the joining means which cooperates with a suspension connection or a click connection in the other element.
It is preferably provided that the joining means is equipped with a threaded section with cooperates with a threaded borehole on or in the other element for fastening to the other element.
Preferably a screw, in particular a cap head screw with a hexagonal head (socket-head cap screw) is used as the joining means. The head of the screw then advantageously has a diameter greater than the diameter of the borehole created in the shear connector. In addition, the head of the screw may be arranged on the side of the shear connector facing away from the other element.
To accommodate the shear connector in the beam, according to a refinement of this invention, a recess running is cut along the longitudinal axis of the beam, preferably having a cross section in the shape of a diamond or a square, extending at least slightly beyond the length of the shear connector. In most cases however, the recess running along the longitudinal axis of the beam will extend over the entire length of the beam, which may be simpler from the standpoint of the manufacturing technology.
For mounting of the element, preferably a beam or girder, on the other element, it is preferable for it to have a recess on the side of the shear connector facing away from the other element, the longitudinal axis of this recess forming an angle with that of the element, preferably the beam, whereby the two recesses intersect. It is provided here to advantage that the angle amounts to between 20xc2x0 and 60xc2x0, preferably between 30xc2x0 and 50xc2x0.
Although a beam is preferably provided as the first element, this invention can equally be applied to any other elements to be joined, in particular flat or rod-shaped components such as boards.
After mounting, the opening formed at the surface of the beam by the recess arranged at an angle may be provided with a closure, in particular a stopper.
A further simplification of the assembly procedure is obtained when a securing element is arranged behind the screw as seen from the contact surface away in the beam, this securing element preventing displacement of the screw relative to the connecting part; the securing element is preferably a pin. It is advantageously arranged at a distance of 5 to 200 mm, preferably 75 to 125 mm, from the end of the screw in the mounted state.
The elements to be joined, in particular beams, may be made of wood, metal, especially steel, or steel-reinforced concrete. It is equally possible to establish a connection to and/or between masonry walls or masonry parts. In addition, one or both of the elements to be joined may be made of plastic. In other words, the joining system proposed here is suitable for a wide variety of applications, especially advantageously in wooden cross-beams in a wooden load-bearing system.
The especially advantageous applications of the joining system are in supporting frameworks and in trelliswork-style constructions as well as in furniture, especially in solid wooden furniture. It is also used to advantage in the manufacture of laminated board materials, preferably in boards composed of multiple layers of wood.
The joining system proposed here permits construction of very simple and inexpensive joints, which can be used for wood-wood joints, wood-steel joints, wood-steel-reinforced concrete joints and wood-masonry joints, for example. This makes it possible to implement dense packings and/or arrangements of multiple beam elements.
It is very advantageous that no visible connections remain with any desired joints. The seal also yields an improved fire prevention effect to advantage.
The joining system according to this invention may also be used to implement and construct wooden structures of multiple floors, in particular two to three floors. This leads to new possibilities in wood construction.
With the joining system according to this invention it is possible to produce not only two connections but also several combined connections. This makes it possible to produce symmetrical or asymmetrical designs, in particular with any desired beam cross sectionsxe2x80x94namely it is possible to produce connections resembling node points in an especially simple manner, where symmetrical or eccentrically positioned elements come together.